Antisense phosphorothioate oligodeoxynueleotides respectively complementary to initial region of 2.1kb mRNA(oligomer A,14nts)and enhancer I(oligomer B,12nts)of HBV were synthesed by chemi cal synthetic method,and inhibition of these oligomers on expression of HBsAg and HBeAg in cell cul ture system was studied. The oligomer A inhibited more than 50％ of HBsAg at 3μmol/L, but the oligomer B did at 6μmol/L. On the contrary,the oligomer B showed 35％ inhibition on expression of HBeAg at 3μmol/L,but 22% the oligo...